Is water sprayed from donkey dung fertilizer considered impure, necessitating the washing of clothes, and does the dung become pure after several days while its substance remains?

Donkey dung is impure. If it is used as fertilizer for trees and some of it splashes onto clothes during watering, then if the impurity of the dung remains, the water becomes impure and must be washed off. However, if the impurity has disintegrated and no trace of it remains, then the clothes do not become impure according to those who hold that impurity becomes pure through disintegration. It is permissible to follow this opinion, though the more cautious approach is to wash what has touched the clothes, in order to avoid disagreement.